toggle

AAPL Stock: 442.16 ( -0.77 )

http://www.macnn.com/articles/05/03/07/basic.alac.decoder/

New decoder for Apple Lossless audio format available

updated 06:50 am EST, Mon March 7, 2005

 

Basic ALAC decoder


One developer has reversed engineered Apple's Lossless Audio Codec (ALAC), a lossless audio codec that retains the full quality of uncompressed CD audio while requiring only about half the storage space. Apple's closed ALAC file format, which previously required iTunes or the iPod or a QuickTime-compatible application for playback, allows users to listen to their ALAC-encoded files in other applications and on other operating systems. David Hammerton's is a C implementation of a decoder based on reverse engineering of the file format. "It turns out that most of the algorithms in the codec are fairly well known. ALAC uses an adaptive FIR prediction algorithm," according to developer. Hammerton notes the release has some limitions--only providing suppor for only 16-bit mono/stereo files, but says that the decoder can easily adapted/upgraded for broader support. The ALAC Decoder can output the decoded file into either PCM or WAV files.


by MacNN Staff

Post tools:

TAGS :

 audio

Related Articles

Recent Articles

toggle

Comments

  1. beeble

    Fresh-Faced Recruit

    Joined: Mar 2004

    0
    03/07, 09:36am | report spam | Reply |

    The point is...

    Since you can do this using the Quicktime SDK on Windows and Mac, what's the point? You can have full support and stay current will all changes Apple make to the codec and dozens of others or you can limit yourself with some reverse engineered hack. Hmmmmmm. That's a tough choice.

  1. horvatic

    Fresh-Faced Recruit

    Joined: Apr 2002

    0
    03/07, 09:50am | report spam | Reply |

    Reverse engineering can

    Reverse engineering can get you in trouble. Why do I need a hack of something that's already out there by Apple.

  1. msconvert

    Fresh-Faced Recruit

    Joined: May 2002

    0
    03/07, 10:19am | report spam | Reply |

    Why?

    this means that now non-ipod players and non-iTunes software can play the files. What is wrong with that?! People will be more likely to use the format if it isn't locked and restricted by Apple. With a larger user base it will become an acceptable format by lots of people and that is good for apple.

  1. Mooseyard

    Fresh-Faced Recruit

    Joined: Jan 2001

    0
    03/07, 12:53pm | report spam | Reply |

    Squeezebox, SoundBridge

    In particular, this means media-server stereo components such as the Squeezebox (www.slimdevices.com) and SoundBridge (www.rokulabs.com) can now play Apple Lossless files.
    All that's required is to build the ALAC decoder and update the SlimServer settings to handle Apple Lossless files by piping them through the decoder.

  1. loudpedal

    Forum Regular

    Joined: Oct 1999

    0
    03/07, 12:59pm | report spam | Reply |

    Just wait...

    ...and I'm sure that Apple is studying their code and will find a way to make this stuff suddenly incompatible in a future release. I don't know why people waste their time on this stuff. Apple has shown to vigorously go after people who try to circumvent iTMS. I'll just stay with the original.

  1. sosumi

    Fresh-Faced Recruit

    Joined: May 1999

    0
    03/07, 07:01pm | report spam | Reply |

    Loser...

    loudpedal, that is a g** attitude. I don't know why you waste your time on these forums. Just stay with the original, try nothing new, and keep your head shoved so far up your a** it'll take you 20 years to get it out.

    People waste their time on this stuff because they are intelligent and have a different idea than the original manufacturer. It's called being innovative. That is in the dictionary just after imbecile and impotent, words which I'm sure you are very familiar.

  1. LouZer

    Fresh-Faced Recruit

    Joined: Nov 2000

    0
    03/07, 11:07pm | report spam | Reply |

    Re: loser

    Hey, I thought I was the loser!

    And its not a stupid position. People do this are smart, but they're also known to waste their time on stuff. Apple Lossless is closed, but you can use Quicktime to do this. So Squeezebox, or musicmatch, can just use Quicktime to play the files.

    On top of that, if someone is so concerned about the playabilty of these files, why in the world did they convert them to Apple lossless in the first place, when they could have used one of several other OPEN formats already out there that are lossless. We're not talking about people buying stuff from Apple then wanting to play it on their Linux box (although there again why'd they buy from apple, but that's another argument). Wouldn't you just be better off writing a ALAC->FLC type converter and get it into a format that you know will work in third-party players?

  1. Ralf_Wiggum

    Fresh-Faced Recruit

    Joined: May 2002

    0
    03/08, 05:03am | report spam | Reply |

    Linux

    "Since you can do this using the Quicktime SDK on Windows and Mac, what's the point?"

    I don't use Windows, or a Mac. I use Linux. That's the point.

  1. testudo

    Forum Regular

    Joined: Aug 2001

    0
    03/08, 09:28am | report spam | Reply |

    Re: Linux

    I don't use Windows, or a Mac. I use Linux. That's the point.

    Stupid point, because if you use that platform, (a) how did you get the music in Apple lossless in the first place, (b) why did you put it in that format if you weren't planning on sticking with windows/mac, and (c) since you have it in that format, wouldn't it be far easier to just convert it on your mac/windows machine that you used in the first place to encode it, and re-encode it in a standards format?

    I mean, come on, anyone using Linux is all 'open this' and 'open that'. They wouldn't use a closed format to begin with.

    Look how many still whine because the iPod can't do ogg files.

Login Here

Not a member of the MacNN forums? Register now for free.

 
close
Photo
toggle

Network Headlines

toggle

Most Popular

MacNN Sponsor

Recent Reviews

MaxUpgrades MaxConnect for 2006-2008 Mac Pro

Nobody outside of Cupertino's privileged bunch knows the future of the Mac Pro line for sure. Despite Apple's reluctance to tell us wh ...

Brother HL-3170CDW LED Printer

We've mentioned before that we are far from a paperless society. For now, at least, there are tasks that require a piece of paper for ...

HTC One

It is hard to overstate just how critically important the HTC One is to the Taiwanese company’s fortunes. Despite its alarming decline ...

toggle

Most Commented

 

Popular News